Calendopaedia - Counting Years

How were years counted in the past?

The most common method of counting years was to count from the beginning of
the rule of the King, Emperor or leader. This system is known as Regnal Years
(see below). The Romans counted from the start of the reign of the Emperor or
Caesar and reset to one when the next Emperor took over. Alternatively they
counted from the founding of Rome. This was indicated
by the letters AUC which stood for ab urbe condita.

To learn more about when the year actually started please see the
New Year page.

Regnal Years

Regnal years are a method of counting years from the date that the
monarch came to the throne. In mediaeval England regnal dates were
normally used to date events and documents. They were still used for
dating Acts of Parliament until 1963.
To take an example King George the 1st was crowned on
1st August 1714. Days from 1st August 1714 to
31st July 1715 inclusive will be in his first regnal year - and so on. So
10th September 1718 was referred to as 10th
September 5 George I. That is the 10th September which fell in the
5th year of the reign of George I.

How do we count years?

In about AD 523, the papal chancellor, Bonifacius, asked a monk by the name of
Dionysius Exiguus to devise a way to implement the rules from the Nicean council
(the so-called "Alexandrine Rules") for general use. Dionysius Exiguus (in
English known as Denis the Little) was a monk from Scythia, he was a canon in
the Roman curia, and his assignment was to prepare calculations of the dates of
Easter. At that time it was customary to count years since the reign of emperor
Diocletian; but in his calculations Dionysius chose to number the years since the
birth of Christ, rather than honour the persecutor Diocletian. Dionysius (wrongly)
fixed Jesus' birth with respect to Diocletian's reign in such a manner that it
falls on 25 December 753 AUC (ab urbe condita, i.e. since the founding of Rome),
thus making the current era start with AD 1 on 1 January 754 AUC. How Dionysius
established the year of Christ's birth is not known, although a considerable
number of theories exist. Although Dionysius proposed this system of counting it
was not generally accepted.

When The Venerable Bede
(673-735) wrote his history of the early centuries of
Anglo-Saxon England he adopted the system of Dionysius and its use spread until
it became a de facto standard.

Was Jesus born in the year 0?

No. There are two reasons for this:

There is no year 0.

Jesus was born before 4 BC.

The concept of a year "zero" is a modern myth (but a very popular one). Roman
numerals do not have a figure designating zero, and treating zero as a number on
an equal footing with other numbers was not common in the 6th century when our
present year reckoning was established by Dionysius Exiguus (see above).
Dionysius let the year AD 1 start one week after what he believed to be
Jesus' birthday. He designated years before 1 AD as being Before Christ (BC).
Therefore, AD 1 follows immediately after 1 BC with no intervening
year zero. So a person who was born in 10 BC and died in AD 10, would have died at
the age of 19, not 20. Furthermore, Dionysius' calculations were wrong. The Gospel
of Matthew tells us that Jesus was born under the reign of king Herod the Great, and
he died in 4 BC. The actual date of his birth is unknown but it was probably in the
region of 7 - 4 BC. The month and day are also unknown.

Does the lack of year zero cause a problem?

Yes it does to astronomers who frequently use another way of numbering the years BC.
Instead of 1 BC they use 0, instead of 2 BC they use -1, instead of 3 BC they use
-2, etc.

What date did other calendars give when we started the year 2000?

Please note that I am not suggesting that this date is start of the new millennium, I
know that that occurred on 1st January 2001.